The present invention relates to athletic shoes, and in particular to spikes for athletic shoes that provide good traction in the forward direction, resist twisting, and that minimize the number of spikes which must be fitted to a shoe.
Athletic shoes for various sports, including track events, are fitted with spikes to provide traction for accelerating and stopping, and to resist twisting of the shoe. Athletic shoe spikes are provided in various shapes and arrangements depending on the requirements of the particular sport. Track shoes are typically fitted with a large number of tapered spikes which may be conical or wedge-shaped such as shown in U.S. Pat. No. 4,546,559 to Dassler, or in U.S. Pat. No. 4,569,142 to Koskela. As exemplified by those references, prior art shoes typically include a relatively large number of spikes due to inherent limitations in the traction provided by the individual spikes. However, minimizing the weight of an athletic shoe is always of primary importance. This is true of track and field shoes in particular. Weight could be removed from track and field shoes if an improved spike were available which provided the required traction with fewer spikes. A need therefore remains for an improved spike for athletic shoes which provides improved traction and stability, and which provides for an overall weight savings.
It is therefore an object of the invention to provide a spike for use in athletic shoes which provides improved traction.
It is a second object of the invention to provide a spike which reduces the overall number of spikes required to provide adequate traction and stability in athletic shoes.
It is another object of the invention to provide a spike which is omnidirectional.
It is another object of the invention to provide a spike which is readily and economically manufactured.
It is yet another object of the invention to provide a spike which can be affixed to an athletic shoe sole by conventional means, or which in the alternative can be formed integrally with a shoe sole.
The present invention is embodied in a spike for use with athletic shoes which includes a distal portion with a generally z-shaped cross-sectional shape. The z-shaped distal portion includes a first, central elongate portion with second and third elongate portions extending angularly therefrom. In the preferred embodiment, the second and third portions are parallel, or nearly so. However, the invention is not limited to a spike in which the second and third portions extend from the central portion at any particular angle, or at equal angles. A spike according to the invention may be integrally molded with the sole, or may be a separate structure that is attached to the sole by an adhesive or by a threaded base portion. The invention is not limited to a spike formed of any particular material, although a metal-ceramic or a polymeric material is preferred.
These and other objects and features of the invention will be described with reference to preferred embodiments of the invention, and with reference to the accompanying figures.